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Flooding Be prepared! The purpose of this leaflet is to outline the various roles and responsibilities and what you need to do to protect yourself and your property from flooding. There are also telephone numbers and websites where you can get more information about flooding. FLOODING What is it? What can we all do about it? Nobody can stop the risk of flooding entirely. Instead a joint effort between the Council, the Environment Agency, Thames Water, Riparian Owners, residents and the community is needed so that we can reduce the risk and impact of flooding. This involves having a greater awareness of local flood risks, having regular maintenance of our water channels and being prepared to respond to a flooding incident should it happen so we can reduce the impact. In West Berkshire we can be affected by a number of types of flooding: River Flooding (Fluvial) This is flooding as a result of rivers and streams overtopping their banks. In West Berkshire we are lucky to have a number of beautiful water courses running through our area. However this can result in properties within flood plains being flooded in periods of heavy and/or prolonged rainfall due to the rising waters, rapid thaw of snow on the ground, or from water coming up through the ground. Flash/Surface Water Flooding (Pluvial) This flooding occurs during periods of extremely heavy rainfall, often over short periods. This can be due to drains being blocked, the ground being already saturated, or extremely dry causing run off or due to the sheer volume of water causing 'flash' flooding in areas not normally prone to flooding. It is difficult to predict where this type of flooding may occur. Groundwater Flooding This is flooding caused as a result of excess rainwater filling up aquifers after it has filtered through the soils. How far below the surface it goes depends on various factors relating to the area you live in, including the geology of the land. In West Berkshire we have areas in the Lambourn Downs that could be affected by groundwater flooding. The Environment Agency monitors groundwater levels and if necessary, underground pumps are used to reduce water levels and therefore the risk of flooding. In some circumstances however it may be that flooding may still occur. The first sign of groundwater levels rising will be evident as flooding in your cellar or water in low lying land or ditches. Who is Responsible for What? Drainage Systems Drains: are pipelines which move foul sewage or surface water runoff from a single property. A drain is still a drain, even if it passes outside the property boundary and until it joins a sewer. Maintenance is the responsibility of the property owner. Inspection Chambers: are chambers constructed on drains at changes of direction or level in the pipeline and for the purpose of gaining access for maintenance. Maintenance is the responsibility of the owners. Highways Drains: are pipelines which move surface water runoff from the public highway only. Highway drains discharge to public sewers, water courses, rivers and often a combination of all three. Maintenance is the responsibility of West Berkshire Council. Highway Gullies: receive surface water runoff from the highway. They trap minor debris and are linked to highway drainage systems. They normally have some water sitting in them. Maintenance is the responsibility of West Berkshire Council. Highway Grips: are small channels cut through highway verges to convey surface water run off from the highway directly to roadside ditches or watercourses. Maintenance is the responsibility of West Berkshire Council. Sewers: are pipelines which move foul sewage or surface water runoff from more than one property. They are normally the responsibility of Thames Water. Manholes: are chambers constructed on sewers at changes of direction or level in the pipeline and for the purpose of gaining access for maintenance. For manholes on public sewers maintenance is the responsibility of Thames Water. Culverts: are pipelines usually of a fairly large diameter (450mm or greater) which move surface water, land drainage or river water through a catchment area to an outfall such as a river or other major watercourse. Many watercourses have been culverted but this does not make them sewers. Maintenance is generally the responsibility of the Riparian Owner except where they pass under highways where responsibility passes to West Berkshire Council. Thames Water is responsible for maintenance of some culverts but not in all cases. Trash Screens: are metal grills fixed across the entry points to culverts to prevent children and animals gaining access and to prevent debris being washed in. Maintenance depends on the precise location but is generally the responsibility of either Thames Water or West Berkshire Council. Balancing Ponds: are large concave areas of open land designed to temporarily accommodate excess surface water when a rain storm generates runoff in excess of the capacity of the piped system. Responsibility for maintenance varies and may be Thames Water, Local Council, Highway Agency or private landowners. Open Watercourses Ditches: are channels, usually man made, cut for the purpose of conveying surface water runoff to streams and rivers. Maintenance is the responsibility of Riparian Owners. Roadside Ditches: these are the responsibility of the adjacent landowner even it they are outside the property boundary. Maintenance is the responsibility of Riparian Owners. The only exception is if they have been dug by the Highway Authority - either West Berkshire Council or the Highways Agency depending on who maintains the road, specifically for the purpose of draining the highway. Streams: are usually naturally occurring watercourses which tend to meander through open land, receive surface water from the surrounding land and ditch networks and discharge to the river system. Maintenance is the responsibility of Riparian Owners Main Rivers: There are seven main rivers which flow through West Berkshire. They are the Thames, Kennet, Lambourn, Pang, Enborne, the Foudry Brook and Sulham Brook. The maintenance of these rivers is the responsibility of the Riparian Owner. The Environment Agency have permissive powers to carry out maintenance on parts of these rivers, where funding and resource allow, to reduce flood risk. Flood Plain: Is a natural feature and is defined as an area of land along the course of a river valley that has historically been the subject of flooding. 7% of West Berkshire area is in flood plain. The responses of flood plains remains with the landowners. Canal: The Kennet & Avon Canal which passes through West Berkshire takes two forms. The major part was entirely man made whilst the remainder was formed by canalising the existing river. Maintenance of the entire canal and maintenance of the man made sections is the responsibility of British Waterways. Responsibility for maintenance of the canalised sections of the river is the responsibility of the Riparian Owners. Sluices: Sluices: are control structures on watercourses, primarily on the rivers and canal. They were constructed to control water levels and the flow volumes. Maintenance is the responsibility of the individual owners. In some circumstances the Environment Agency has certain powers or agreements to operate the sluices. Riparian Owner & Responsibilities Riparian Owner You are a Riparian Owner under common law if any river or watercourse lies within or adjacent to the boundaries of your property. Where a watercourse is between your property and an adjacent property you may have joint riparian responsibilities. The watercourse may range from a reasonable sized ditch/river with a constant flow to nothing more than a depression which carries water infrequently. Watercourses may also be piped. Land Drainage Authority West Berkshire Council is the local Land Drainage Authority under the Land Drainage Act 1991. The Act gives the Council the power to deal with obstructions in ordinary watercourses where that obstruction to the flow of water creates a risk of flooding. In order to use the powers the Council has a policy relating to the formal action process which includes service of notices on landowners through to doing the works and then recovering the costs from the riparian owner. Responsibilities of Riparian Owners You are responsible for: maintaining the bed and banks of the watercourse including trees and shrubs growing on the banks, and for clearing any debris, natural or otherwise allowing water to pass on without obstruction, pollution or diversion affecting the rights of others and you must not cause any obstruction to the free passage of fish keeping the bed levels clear of matter that could cause an obstruction, either on your land or by being washed away by high flow to obstruct a structure downstream. The Rivers and their banks should not be used for the disposal of any form of garden or other waste. keeping clear any structures that you own such as culverts; trash screens weirs and sluice gates. In addition You have to accept flood flows through your land. You may have flood defences such as walls and embankments on your property which are vital for the protection of both yourself and others. You should discuss the maintenance of such defences with the Environment Agency, in the case of main rivers, and in the case of all other watercourses, with West Berkshire Council. You may have flood defences such as walls and embankments on your property which are vital for the protection of both yourself and others. Planning and F lood Reduction There are policies to try to design out flooding when there are new developments or changes to existing structures of buildings including new drives. This falls into two areas: Planning Applications for new developments On receipt of any planning application made to the Council one of the considerations is in relation to Flooding.